Terminal clamp



April 1957 J. G. HUMMEL 2,789,276

' TERMINAL CLAMP Filed April 15, 1954 IN V EN TOR.

95/721 (9. Hummel BY fliforfley.

United States Patent TERMINAL CLAMP John G. Hummel, De Witt, N. Y.,assignor to Crouse- Hinds Company, Syracuse, N. Y., a corporation of NewYork Application April 15, 1954, Serial N 423,487

2 Claims. (Cl. 339-272) This invention relates to terminal clampsemployed to detachably connect electrical conductors to the terminals ofelectrical apparatus.

In general, this type of connector consists of a tubular or bOXlll-lbody portion for the reception of the end of the conductor which isclamped therein by a plate actuated by a screw threading into the body.In prior devices of this kind, the clamping plate is apertured torotatably receive the inner end of the screw, the plate being swiveledon the screw by the inner end of the screw being headed or swedged overthe plate. In some structures, the plate is interfitted with the body ofthe terminal so as to have sliding movement relative thereto in adirection axially of the screw. These arrangements are to preventaccidental displacement of the plate from the body of the terminal. Suchconstructions are expensive to manufacture.

This invention has as an object a terminal clamp of the type referred toembodying a structural arrangement whereby the conductor clamping plateis afiixed swivel fashion to the actuating screw without riveting orinterconnecting the clamp plate to the body of the terminal.

The invention consists in the novel features and in the combinations andconstructions hereinafter set forth and claimed.

In describing this invention, reference is had to the accompanyingdrawings in which like characters designate corresponding parts in allthe views.

In the drawings Figure 1 is a plan view of the contact unit of a plug orreceptacle provided with terminal clamps embodying my invention.

Figure 2 is a side elevational view of the structure shown in Figure 1,the left portion of the figure being shown in section taken on line 2-2,Figure 1.

Figure 3 is a side elevational view of one of the terminals shown inFigures 1 and 2, the upper portion being shown in section.

Figure 4 is a side elevational view of the actuating screw, the innerportion thereof and the clamp plate being shown in section.

Figure 5 is a plan view of the clamp plate and actuating screw.

The terminal clamp consists of a tubular body attached to a circuitforming element of an electrical apparatus. As here shown, the body 10is attached to the end portion of a contact 11 of the type commonlyemployed in plug and receptacle units. These contacts are mounted in abody or contact carrying member 12 formed of insulating material.

The tubular portion 11, shown herein, is rectangular in cross sectionand is mounted in a rectangular recess 13 formed in the supportingmember 12. The tubular body is formed with a threaded aperture in one ofits side walls 2,789,276 Patented Apr. 16, 1957 to receive an actuatingscrew 14, the inner end of which is formed with a stem 15. The end ofthe conductor 17 is positioned in the tubular body 10 and is fixedlyclamped therein by a plate 18. The central portion of this plate isapertured and depressed on opposite sides of the aperture to form a pairof confronting tongues 20. The tongues 20 extend lengthwise of the plateand are inclined from the plane of the plate 18 toward the screw 14, andwith the confronting end edges of the tongues initially spaced apart asufficient distance to receive the enlarged head portion 22 of the stem15.

The plate 13 is positioned within the tubular member 10 and the screw 14threaded inwardly, the head portion 22 of the stem 15 passing betweenthe confronting edges of the tongues 21), and as the plate is movedagainst the opposite side wall of the tubular member, the tongues 20 aremoved inwardly toward the plane of the plate 18, thus reducing the spacebetween the confronting edges of the tongues, whereby the head portion22 overlies the inner surface of the tongues and accordingly, the plateis swiveled to the screw without any riveting or swedging operationperformed on the stem 15.

Preferably, the tubular member 10 is formed with a cylindrical bore 25and the plate 18 has a widthwise dimension somewhat less than thediameter of the bore of the body, and the plate 18 preferably has alengthwise dimension substantially greater than the diameter of the bodybore 25, whereby the plate is maintained in axial relation to the boreof the body 10. With this arrangement, it is not necessary to provideany interfitting sliding structure between the plate 18 and the bodymember 10 and, as previously pointed out, the riveting operation for'aflixing the plate to the screw is avoided. Preferably, the

inner surface of the plate is serrated as at 27 to provide a firm gripon the conductor 17.

What I claim is:

1. A terminal clamp comprising a tubular body having a threaded aperturein the side wall thereof, a screw threaded through said aperture andbeing formed at its inner end with an axially extending stem of reduceddiameter and having an enlarged head portion at the end thereof, aconductor clamp plate positioned in said tubular member, said platebeing formed with a pair of aligned deformable tongues with theirconfronting ends spaced apart a distance slightly greater than thediameter of said stem and being initially inclined from the plane of theplate towards said screw, with the confronting ends of said tonguesspaced apart to admit passage of said head portion of the stem forengagement of said tongues by said screw whereby, upon tightening saidscrew, said tongues are moved into the plane of said plate to retain thesame on said stem for swivel action relative thereto.

2. A terminal clamp as defined in claim 1, wherein the widthwisedimension of said clamp plate is substantially less than the diameter ofthe body bore, and the lengthwise dimension of said plate issubstantially greater than the diameter of the body bore.

References Cited in the file of this patent UNITED STATES PATENTS1,520,702 Durham Dec. 30, 1924 2,201,674 Rowe May 21, 1940 2,265,911Landmeier Dec. 9, 1941 2,727,220 Buchanan Dec. 13, 1955 FOREIGN PATENTS23,877 Great Britain of 1912

